Answer:
Length = 25 cm
Breadth = 10 cm
Explanation:
Let breadth of the room be 'x'
Let length of the room be '
'
Perimeter ( P ) = 70 cm
Now, let's find the breadth of the room 'x '
Perimeter of rectangle =

plug the values

Collect the like terms

Calculate the product

Swap the sides of the equation

Divide both sides of the equation by 7

Calculate

Breadth = 10 cm
Now, Let's find the length of the room ' 2.5x '
Length of the room =

Plug the value of X

Calculate the product

Thus , The length and breadth of the room is 25 cm and 10 cm respectively.
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